Curved surfaced body of fiber-cement concrete and method of molding it



Patented Nov. 14, 1922. j 2.

S. A. WlLLIAMS.

nPPLlcmon msn :un: 9.19m.

cunven sumcen nouv or FIBER CEMENT concimi, Ano METHOD or Mmmm; lr.

' a mixture of short asbestos fiber, or eshesti-` required, to p land cement, is the type. H i li ter ressthe roductimmedatel inolldiug operall -lowed to set-in `the ldesired curved iornnthe molded' method of operation and mi s. params or essere @Meer orties.,

Patented Nov. i4, 1922.

" UNHTED STATES mum. a, wrnmsus, or. ricorrono; new vom;

oneven sunrncnn Bonr or' rrnnnecnnnur 'oo'ncnnrn AND irnrnon or HOLDING rr.

` spermine medien s, isti: sei-isi no. 476,201. Y

performed and also in theproduct of the Be it known thatI, SAMU-,en A. WILLLAMB, method. All will be herein described, and a. vsubject of the King of GreatBritain and the method and productie herein claimed; resident of Loc rt, in the county of iagthe mechenis'mis the sub'ect of claim in en ara end State o New York, have ,invented application for United tetes Letters Patnew and useful Im roveinents in Curved ont Iiled b' me concurrently herewith, se` Sui-faced Bodies of iber-Cement Concrete rallyV num ered 476,202.

This methA d is applicable to the To allwhom it may concem:

and Methods of Molding Them, of which reduc. the following is a specification. tionotregularly orirr larly curbed7 bodies ofV cylindrical My invention relates to the art of forming other curved rassure-molded articles of4 compounded brons and cementtious material, of '.yvhil'i form ber reduced by 'grinding se'rpen` tine with a ydraulic coment, such, as P ortpressure is structurally rodeo@ dense en.. stro sl bs, sheets or block xiV of auch ma illustrate diagrammlatically tori gusually this ressuregis appliedjoa with; which finy new method may e pracwetmixture ofthe er and cementina fllticed, r

after the lA shows e. mold andbottom convex sup Aorted until uct known as asbestoswood is made 1n thismenner. 'Heretofore'wliencurvedsurfaced products of lthis character have been 'required sheets of the com ite me teria1- hash from the press, an` therefore exible, have been be t over forms, and alshape 'thus` imparted. Attempts to mold bodies of such material in curved-surfaced, filter presses have not tion; met with success; in order to preserve 'the Fig?, the bottom die in its elevated posibody had tion, andthe molded body ready to be re to remain inthe press until set, andthe movedgin cross section; and intimacy with whichthe molded material Fig.i 8, a molded product, 1n perspectiye. clungto the perforated orreticulated ,f il- Suppose, for-example, that the material ter press plate made it next to impossible to lbe molded consists ofthoroughly mixed toremove 'the molded body without injury asbestosher (or 4ground serpentine) Port to Ait, or to the lter hed, or both. lend cement, and that Quantity 4of water in to be die, in cross section;

The AFig. 2, the same in longitudinal section;

Fig. .3, the seine in plan view; Figc, themold, bottom convex die, and temping plunger, inoross section;

Fig. .5,v the Hsaine, ith. the' tamping plunger in operaton'in the ber-concrete materiel; Fig. 6, the mold, bottom andltop dies, and material. after compression, all in cross secthe cement has set.

There is frequent need forcurved shapes of material of this character, as for ridgeccriieni., i; e., about .Fifteen per cent of the rolls which are used withasbesto's shingle weightof the cement, and thatlthe' molding or tile, in roon end heretofore such by'pr'essure is to reduce the volume of the tro,y hshaped bo les have been mede by mixtl'u-e to about one third of i ts bulk in ben fresh or green composite asbestos the loose. and 'that .the characteristic cross- [ber board over a. form and allowing it to section of .he final molded body is semist in the shape im a circular', as indicated :it m in Fig. 6. This My'invention hasor its object 'theinanuwill ,be characteristic, whether the whole facture of curved-surfaced and concavebody'be' semi-cylindrical, oi' hemisplierical, convex bodies oi composite fiber and cement, oi' conical, o r conoid'ajl, etc. represented by the asbestos fiber and li'ydraulic cement compositions, more expedi- I `he mold 'o oinprisesV a box, with parallel vertical.sides a, n, tously than formerly, end consists in a of' curved cross section (see material m,

mechanism by which' the me ed can be which is the minimum requisite to set the tece- For 'obvious mechanica-I `ramaons'gligaci: cqm- @von he fini.-

.A vao Iss M' so prises depositing the concrete material over a. convex mold-member, imparting a stepped conformation to the material by condensing portions thereof at the sides of the convex mold member, and thereafter changing said stepped conformation to curved conformation by pressure in resultant direction subtantially normal to the convex mold-mem- 4. The method of molding fiber and cement concrete bodies in shapes characterized by curved cross section, which comprises forming a concrete mixture with substantially the proportion of water requisite to set the cement, depositing the concrete material over a convex mold-member, imparting a stepped conformation to the material by condensing portions thereof at the sides of the convex mold-member, and thereafter changing said stepped conformation to curved conformation by pressure in resultant directions substantially normal to the convex mold-member.

5. Fiber-and-cement concrete pressurecompacted body, characterized by curved surfaces compressori to homogeneous density and internal homogeneous structural continuity by preliminary condensation of edge portions in a direction substantially tangential to the curvature of the body, and final condensation by pressure substantially normal to said curvature at all points.

6. Fiber-and-cement concrete pressurecompacted body`r characterized by concavo convex form, compressed to homogeneous density and internal homogeneous structural continuity by preliminary condensation of edge portions in a direction substantially tangential to the curvature of the body, and final condensation by pressure substantially normal to said curvature at all points.

Signed by me at Boston, Massachusetts, this fourth day of June, 1921.

SAMUEL A. WILLIAMS. 

